Walking on Boiling Water: the geothermal fields of New Zealand

18-19 March 2015. Tripadvisor describes it as one of the Twenty surreal places you need to see to believe. I’d been there forty years ago but have little memory of it except for the steam rising from the ground and the rotten-egg smell of sulphur.

When we first enter Waiotapu (Maori for sacred waters), we are drawn into a grey and white craggy steamy landscape, white cliffs of textured chalk, grey and ochre-coloured deep jagged pits, steam rising from caverns in the ground, steam coming from small sulphur-covered vents, and pools of boiling mud. In places the earth is black, and boiling. We are immediately aware of the restlessness of the earth beneath us.








As we walk further we come to a spectacular dreamlike wonderland of steaming coloured pools with hot water flowing everywhere. It is at once dazzling and eerie. In all directions are land and water formations that almost defy description.






Walking through this extraordinary setting we are spellbound and incredulous. I’m astonished by the surreal beauty, and by the immense variety of colours. And I’m madly puzzled. I don’t understand. What creates such a landscape? There are scientific explanations of course, but somehow they seem abstract and lacking in soul. We have entered an alien world. Any explanation would only detract from the experience. At the same time the mind craves understanding.
















Everywhere we walk we can hear the constant sound of boiling liquid, as if there is a huge soup bubbling away on the stove, but eerily it is the Earth beneath us that is boiling.

The geothermal area of Waiotapu covers eighteen square kilometres and is littered with collapsed craters, cold and boiling pools of mud or water, and steaming fumaroles. It is part of the Taupo Volcanic Zone, which stretches in a diagonal line across the centre of the North Island. The zone is 250 kilometres in length and is one of the most active volcanic areas in the world.

Beneath the ground is a system of streams heated by magma. When water is heated under the earth it must find a way to escape, and it frequently does so with breathtaking results. The water is so hot that it absorbs minerals from the rocks and transports them to the surface. Yellow is from the presence of sulphur, green from ferrous salts.








The earth’s crust is made up of a number of interlocking plates, which move independently like giant icebergs. New Zealand sits astride an active fault line where two of the earth’s plates are relentlessly colliding. In the South Island they meet and push upwards to form the Southern Alps. In the North Island one plate is pushing underneath the other, which creates a colossal amount of active subterranean heat and volcanic activity. We see the consequences of this subterranean activity all around us.



The green on the left in the picture above is the edge of the Champagne Pool. The orange is created by the presence of antimony. The Champagne Pool was formed nine hundred years ago by a hydrothermal eruption. The resulting crater, filled with bubbling water made green by ferrous salts, is 213 feet in diameter and 203 feet deep. The water is 163 degrees Fahrenheit, or 73 Centigrade. The water below the earth is 500 Fahrenheit or 260 Centigrade. It’s barely comprehensible.

We thought we’d seen it all only to then arrive at this pool of milky intense chartreuse liquid. It is known as the Devil’s Bath. The colour of the water in this crater is the result of excess water from the Champagne Pool mixing with sulphur and ferrous salts.






To reach Orakei Korako, “The Hidden Valley”, we take a short ferry ride across the Waikato River. We thought Waiotapu was spectacular, but it was just the prelude. The scene at Orakei Korako leaves us gaping. Bright orange and green terraces, white cliffs, water-filled craters, boiling mud, boiling water, and orange and white land formations that appear to flow as if they are liquid. The Earth seethes and boils around and beneath us, the underground heat creating a landscape of unique beauty.




















From the website of Orakei Korako: The hot springs, geysers and clear blue pools at Orakei Korako discharge alkali chloride water. This water ascends quickly to the surface from deep reservoirs where the temperature is hotter than 175°C. Upon discharge at the surface these waters cool. As they cool below 100°C, the silica that is carried in the water is deposited at the surface, forming the white silica sinter terraces. Sinter is rock that is formed over time by the deposition of silica from thermal water. Silica sinter is unique in the way it is not buried, yet it still transforms into rock. Different types of microbial mats cover the sinter terraces, the colour indicating the type of microbe.

The microbes, tiny single-celled organisms, vary in colour according to the temperature of the water. Unlike the orange and green colouring at Waiotapu, which come respectively from antimony and ferrous salts, the orange and the green seen on the sinter terraces at Orakei Korako comes from the microbes. Orakei Korako has the largest silica terraces in the world, and at least twenty active geysers.

We visit one more area in the vast geothermal field of the central North Island, the Whakarewarewa thermal valley. The name is Maori for the gathering place. Whaka-rewa-rewa. Maori words are not so difficult if you break them down into sections, but even the locals reduce it to Whaka. Pronunciation, now that’s a whole other issue.

Once again we are met with an exotic sight: flowing water, flowing rocks, strange formations, bright sulphur pockets, pure aqua pools, and orange microbial growths.












The most extraordinary jaw-dropping experience of the entire geothermal excursion is beyond doubt the Pohutu Geyser.

There are many geysers in the New Zealand geothermal fields. They are formed when pressure builds as the water underground reaches higher and higher temperatures and is then forced out through a very narrow opening. The result is a fountain of very hot water and steam. The Pohutu Geyser erupts up to twenty times per day, and sends steam and water as high as thirty metres, or one hundred feet, into the air.

We are standing by the barrier waiting and waiting. Many in our group have wandered off, but most of us are waiting, determined to see what all the fuss is about. At first it starts bubbling and steaming. It looks a little like soapsuds frothing up on the rocks. We continue to wait. Is that it? Then it gets a little stronger, a little higher, but it’s still not all that spectacular. We wait some more. And then it goes. With a giant whoosh it explodes higher and higher into the sky, yes, as high as thirty metres. I’m afraid it will stop any second and that it will be over before I’ve had a chance to really take it in. But no. It goes on and on, shooting into the sky. A giant natural fountain of boiling water and steam. We watch for fifteen or twenty minutes and it’s still going when we walk away completely awed. My photo can give only a hint of the reality.




Never for a moment think that the Earth is solid or still. The Earth beneath us is all powerful and is always moving.

Of course a visit to the geothermal fields would not be complete without a soak in a hot spring, which we did of course: a sweet luxurious ending to one of our days of exploration.

Next post: A deer farm, Stu the pig man, and some wildly creative garments from the matchless World of Wearable Art.






All words and images by Alison Louise Armstrong unless otherwise stated.
© Alison Louise Armstrong and Adventures in Wonderland – a pilgrimage of the heart, 2010-2015.